My tempo runs are my easy days. Tempo to me means getting your legs back under you temporarily during the week where you have three other hard runs (intervals, progression, long run).
My week.
Monday - 5 Mile Tempo
Tuesday - 6x800 Intervals
Wednesday - OFF
Thursday - 8 Mile Progression Run
Friday - 6 Mile Tempo
Saturday - 5 Mile Tempo
Sunday - 12 Mile Long
My Tempo runs are temporarily slower than my hard workouts.